Patent GB-712036-A (GB)
Title: Improvements in or relating to yarn supplying and changing mechanism for knitting machines
Inventor: STIBBE GODFREY DENNIS
IPC: D04B9/10
Filed: 1950-12-07
Abstract: 712,036. Knitting-machines. STIBBE & CO., Ltd., G., STIBBE. E. V., and STIBBE, G. D. Sept. 17, 1951 [Dec, 7, 1950], No. 29997/50. Class 74 (2) One or more yarns Y may be fed at a time from individually and selectively, operable yarn guides 1, movable between high, intermediate and low feeding positions a, c, b and a lowermost, non-feeding position d, as the toe of an associated lever 4 rides from the face of a drum 3 on to cams of increasing height. Five guides provide colour changes and a sixth guide feeds heel and toe yarn. Each lever 4 carries abutment screws 6, 7, through which it acts on arm 8 of a lever 9, a second arm 10 of which is fulcrummed to the shank 13 of the associated yarn guide 1. As the yarn guide moves, a profiled front edge if its shank 13 is constrained, by a spring 16, to bear against a plate 14 and thus the path P of the extremity of the guide is made to conform to the contour of the latch guard and the ribs 15a of the sinkers 15. The guides converge towards a common point F and parts 25 thereof are flexible, to allow of lateral deflection as the guides pass one another, to allow of a number of guides being at the knitting location during substitution of yarns from one pair of plating guides by yarns from another pair and whilst making an overlap. A common yarn trapper T comprises a resilient member 28 against which presses, at a slight angle thereto, the serrated end 27 of a spring-loaded blade 26 and a bevelled supplementary blade 30 borne on the blade 26, so that any trapped yarn can be pulled out in the knitting direction only. A portion of the member 28 is tangential to the needle line. Any withdrawn yarn is forced into the trapper by hooks 32, pivoting on a shaftÀ43, at every yarn change. A cutter interconnected with the hooks severs any yarn withdrawn. The cutter comprises a fixed blade 34 co-operating with a blade 35 pivoted at 36 and linked by pin-and-slot connection' 38, 39 with a fulcrummed' trigger 40 actuated by a collar 41 on a rod 42 which is also connected, through a spring 46, with an arm 44 fixed on the shaft 43. Thus, movement of the rod 42 first operates the hooks 32 and then closes the cutter against the action of a spring 50. Yarn guides out of action rest in line; and outgoing yarn is led across the trapper T. To pre-determine the needle first taking a yarn being, introduced, there is provided in the projected sinkers or webholders 15 a gap G in which is located the length of yarn Y<1> extending between the yarn guide 1 moved to feeding position and the trapper T. For this purpose, a panel 15<1> of the sinkers, is only partially projected,'by the action of a low level cam ledge on short butts which they bear; whilst the remainder of the sinkers are fully projected by a higher ledge acting on normal butts. As a result, yarn overlap is substantially positive and uniform in length, no yarn is doubled or wrapped'back at the join and limited single course striping can be carried out. The free ends of the yarns at the join are caught up and knitted in the following courses of knitting. Yarns are individually tensioned and frictionengendering, means obviate any tendency for yarns to race. Heels and toes of seamless hose or half-hose may be made without interfering with or breaking up the sequence of, say, striping colours. The heel and toe feeder is selected separately from the main control drum and, when it is in action, striping is automatically suspended. The control drum 3 has fixed thereto a ratchet wheel 59 racked round by a pawl 60 pivoted on an arm 62. The pawl 60 is disabled; at predetermined times, by engagement of 'a detent 64 with a tooth 63 on the arm 62. Studs 67 on a timing chain 68 act through a lever 66 to rock a shaft 65, as required, to lift the detent 64 clear of the tooth 63. At each completion of a garment, or after a press-off or manual restart, the yarn feeding and changing mechanism is retimed at the dictates of a cam 69 on a timing drum 70, acting through another lever 71 on shaft 65.